Apparatus for spraying glass containers

Abstract: An apparatus for spraying the surfaces of glass containers which are being moved in longitudinally spaced transverse rows by a conveyor (10) wherein a rodless air cylinder (14,15) is mounted transversely of the conveyor (10) and the spraying apparatus is connected to the piston of the rodless cylinder (14,15) so that the spraying apparatus is moved transversely of the rows of containers. The rodless cylinder is supported for pivotal movement about a vertical axis (18a) so that the axis of the cylinder may be moved to a position other than a right angle to the longitudinal axis of movement of the conveyor (10). The offset of the angle from a right angle and the speed of traverse of the piston is coordinated with the conveyor speed so that any time during the travel, the spray apparatus is spraying between the rows being sprayed.

Description: This invention relates to a method and apparatus for applying surface coatings to glass containers. It has been known to provide surface coatings to containers as they are moved in rows that extend transversely of a conveyor on which they are supported by providing an overlying spraying apparatus that is moved transversely to the direction of movement of the rows of the containers. In such apparatus, it is conventional to utilize gearing or chains to move the spray apparatus such as guns transversely of the conveyor. Such apparatus uses a large number of parts, requires substantial time for installation, is expensive to manufacture and maintain and requires complex controls. In an apparatus of the kind referred-to above (US-A-4,024,836, which represents the prior art as referred to in the preambles of claim 1 and 9) the spanning means takes the form of a carriage with a channel member and a beam overlying and crossing the conveyor in an acute angle to the transverse axis thereof so as to follow the rows of containers. One end of the carriage is fixed whereas the other end can be shifted. The control of this type of apparatus is difficult and imprecise in ensuring that the spray apparatus moves between the rows of containers as they are moved by the conveyor. Among the objectives of the present invention are to provide a method and apparatus which overcomes these disadvantages and provides a system for moving spray guns transversely; which provides more accurate movement and control of the spray pattern such that the coating is applied to the surface of the container between the moving rows of containers; which permits acceleration and deceleration from each end of the stroke of the apparatus transversely; which requires minimum maintenance; and which can be utilized in either a continuous mode or a row follower mode. The invention is defined in claims 1 and 9, respectively. A method and apparatus is provided for spraying the surfaces of glass containers which are being moved in longitudinally spaced rows by a conveyor wherein a rodless air cylinder is mounted transversely of the conveyor and the spraying apparatus is connected to the piston of the rodless cylinder so that the spraying apparatus is moved transversely of the rows of containers. The rodless cylinder is supported for pivotal movement about a vertical axis so that the axis of the cylinder may be moved to a position other than a right angle to the longitudinal axis of movement of the conveyor. The offset of the angle from a right angle and the speed of traverse of the piston is coordinated with the conveyor speed so that any time during the travel, the spray apparatus is spraying between the rows being sprayed. Description of the Drawings FIG. 1 is a transverse elevational view of an apparatus embodying the invention. FIG. 2 is a fragmentary plan view taken along the line 2-2 in FIG. 1. FIG. 3 is a sectional view taken along the line 3-3 in FIG. 1. FIG. 4 is a view of a portion of the apparatus shown in FIG. 3 taken at 4. FIG. 5 is a view taken in the direction of the arrow shown in FIG. 2. FIG. 6 is a fragmentary sectional view taken along the line 6-6 in FIG. 5. FIGS. 7-12 are schematic diagrams showing the manner in which an X-pattern spray can be provided for spraying between the rows of containers. FIGS. 13-17 are combined mechanical, pneumatic, lubricating and electric diagrams showing the operation of the apparatus in various portions of a cycle. Referring to Figs. 1-4, the apparatus embodying the invention is adapted to be used in spraying rows of containers C that are moved along the conveyor 10 that may be part of a lehr conveyor used to transport glass containers through an annealing lehr, the apparatus being positioned at the exit of the annealing lehr. The apparatus comprises a frame including supporting columns 11, 12 and transverse beams 13. A pin or support 18 extends horizontally from top beam 13 (Fig. 2 and 6) and carries a vertical axis 18a at its end which cooperates with a bracket 17 fixed to a spray arm 1. The spray arm 1 includes one or more rodless cylinders 14, 15, a spray carriage 16 to be driven by the cylinders 14, 15 and support carriages 19 at the ends of the arm 1. Each carriage 19 is supported on rollers 19a mounted on the frame (Fig. 1). Each cylinder 14, 15 is of the well known rodless cylinder construction which includes a cylinder barrel having a slot along its length. A piston is mounted within the cylinder and is moved by air being selectively applied to one or the other side of the piston. The piston carries a member 2 extending through the slot and a seal seals the interior of the cylinder from leakage through the slot as the piston is moved along the cylinder barrel. The carriage 16 is connected to the members 2 and carries a spray delivery apparatus S which includes one or more spray guns or heads H for directing liquid on the containers. The spray delivery apparatus S is provided with the spray liquids through hoses that are guided by a flexible and foldable track 20. Referring to Figs. 2 and 6, each a fluid cylinder 21 is mounted on the frame and has a piston rod 22 connected to the adjacent carriage 19, so that the angle which the axis of the arm 1 makes with respect to the longitudinal axis of movement of the conveyor 10 can be changed (see Fig. 7) to positions ranging from perpendicular to the conveyor or having one or the other end of the arm 1 leading. As a result, the arm 1 can be moved to what might be termed an X pattern or relationship as may be required . With the arm 1 positioned perpendicular to the conveyor 10, the spray apparatus can be operated either continuously or intermittently to apply the coatings to the containers. Referring to the diagrams shown in Figs. 7-12, the angle and associated speeds of the various components can be adjusted in order to spray between rows of containers C. In Fig. 7, the amount of offset X at the ends of arm 1 to the horizontal row center line 3 is shown. The speed of the spray carriage 16 is determined by the speed of operation of the rodless cylinders across the conveyor 1β. When the speed of the conveyor 10 is set properly to the speed of the spray carriage 16, the spray guns will be positioned between the rows at any time during the travel. Referring to Fig. 8, the center line distance between rows is R and the time required to advance one row (one cycle) is Tr. The row-to-row velocity is Vr = R/Tr . Line 4 connecting the start point to the end point (one traverse) shows how a sprayer must travel to stay between the rows of containers when the conveyor advances the distance R in a cycle. Fig. 9 shows the arm 1 with sprayer H arrived at the end of one traverse. The operation of a reverse traverse is as follows: 1. The arms 1 with air cylinder is set at an angle α, the sprayer waits at end of cylinder on down stream side. 2. The passage of row "A" of containers "triggers" (enables) the sprayer. 3. A wait (on delay) timer allows row "A" to pass before spray cycle starts. 4. The air cylinder receives an air signal which pushes the piston (and sprayer) across the conveyor. The spray arm does not pivot or change angle at this time. 5. The sprayer is set to move at a velocity, V s = C/Tr (by control of air flow) so its motion along vector, FC, carries it forward to reach the opposite side of the arm 1 in time Tr. The vector (angle and speed) accounts for the motion of the bottles forward. 6. When the sprayer reaches the opposite side, the arm 1 pivots, i.e. the sprayer "shifts" so that it can start another full cycle and spray the opposite direction when triggered by the next row. Referring to Fig. 11, the spray arm has pivoted from traverse 4 to traverse 5 and the sprayer has "shifted", ready to spray between the rows on the return traverse 5 of the spray gun carriage 19. Referring to Fig. 12, during operation, if it is necessary to increase V s , such that the sprayer reaches the opposite side in Tr', where 0<Tr'<Tr., the extra time, Tx = Tr-Tr' is used to "shift" the sprayer before the next row starts the new cycle. Accordingly, the angle of the spray arm is set to a smaller angle α'. Fig. 13 indicates the general relative lay out of the various components, the spray arm 1 being shown in a side elevation view, a plan view and a cross-sectional view. Fig. 14 shows the relative positions at the beginning of a cycle. The CYLINDER SOLENOID valve receives a signal from the PROGRAMMABLE CONTROLLER (from the TRIGGER EYE photocell, Fig. 1) to direct air to the right side of the cylinders. Since both cylinders are joined internally, the PISTONS will begin to move simultaneously. The pistons are mechanically linked to the SPRAY CARRIAGE. Referring to Fig. 15, as the RH SPRAY SENSOR is uncovered by a SENSOR BAR when it moves pass the SENSOR, programmable controller energizes the SPRAY SOLENOID to turn the SPRAYER on. As air pushes on the right side of the PISTONS, air on the left side exhausts through the RT TO LFT FLOW CONTROL, CYLINDER SOLENOID valve and EXHAUST PORT. The velocity of the carriage, V s is set by these flow controls. Referring to FIG. 16, as the CARRIAGE reaches the left side, the SENSOR BAR covers the left BRAKE SENSOR, causing the BRAKE SOLENOID to apply air to left side of the PISTONS. The BRAKE air pressure is sufficient to slow the speed of the PISTON/CARRIAGE assembly. The BRAKE air continues as long as the SENSOR BAR covers the BRAKE SENSOR. Referring to FIG. 17, when the SENSOR BAR covers the left SPRAY SENSOR, the sprayer is turned off. The CARRIAGE is slowed even more and finally stopped by the left SHOCK ABSORBER. The SHIFT SOLENOID valve receives a signal from the PROGRAMMABLE CONTROLLER, causing an air signal to be sent to the SHIFT CYLINDER. As shown in FIG. 13, the PROGRAMMABLE CONTROLLER functions to periodically operate a pneumatic piston pump to inject oil at a point where the air enters the air cylinder ensuring that there is a presence of oil on the piston seals when the piston stops at the end of its stroke. It can thus be seen that there has been provided a method and apparatus which overcomes these disadvantages and provides a system for moving spray guns transversely; which provides more accurate movement and control of the spray pattern such that the coating is applied to the surface of the container between the moving rows of containers; which permits acceleration and deceleration from each end of the stroke of the apparatus transversely; which requires minimum maintenance; and which can be utilized in either a continuous mode or a row follower mode.

Claims: An apparatus for applying surface coatings to glass containers (C), comprising a conveyor (10) defining a longitudinal axis and a transverse axis and for supporting a plurality of glass containers (C) in rows that extend transversly, and for moving the containers along the longitudinal axis; frame means (11, 12, 13); means spanning and overlying said conveyor (10) and being supported on said frame means, a portion of said spanning means extending during the coating at an acute angle (α) to said transverse axis; a spray carriage (16) guided along said portion of the spanning means and carrying a sprayer (S); driving means for moving said spray carriage (16) along said portion of the spanning means; actuator means (21, 22) for altering said acute angle (α) between the portion of the spanning means and the transverse axis; and control means for controlling said actuator means; characterized in that said spanning means overlying said conveyor (10) includes a crossing frame member (13) which is a portion of said frame means (11, 12, 13), and a spray arm (1) which is said portion of the spanning means carrying the sprayer (S), said spray arm (1) having two ends is pivotionally connected through a vertical pivotional axis (18a) to said crossing frame member (13) and includes said driving means in the form of cylinder means (14, 15), said vertical pivotal axis (18a) is substantially at the center of the apparatus with respect to the conveyor (10), said control means controls said actuator means (21, 22) so that said arm (1) is pivoted into a first (4) or a second (5) position where that end of said arm which said sprayer (S) has arrived at, is shifted back a row distance (R) relative to the moving direction of said conveyor (10). The apparatus set forth in claim 1 wherein said vertical pivotal axis (18a) is formed by a pin connecting a support (18) to a bracket (17), said support (18) extending horizontally from said crossing frame member (13), and said bracket (17) being fixed to said spray arm (1). The apparatus set forth in claim 1 or 2 wherein said cylinder means (14, 15) comprises a pair of rodless air cylinder barrels. The apparatus set forth in any of claims 1 to 3 wherein said control means include programmable controller means for controlling the movement of said spray apparatus such that the sprayer (S) travels between rows of containers (C) in both directions between both ends of the spray arm (1). The apparatus set forth in claim 4 including lubricating means operable by said programmable controller means for delivering a lubricant to the piston of the cylinder (14, 15) as it reaches one end of its stroke. The apparatus set forth in claim 5 including air brake means operable by said programmable controller for applying a burst of air to opposite ends of the piston as the sprayer (S) approaches the end of the stroke. The apparatus set forth in claim 6 including shock absorber means at each end of the stroke of the cylinder (14, 15). The apparatus set forth in any one of claims 4 to 7 wherein said programmable controller means is responsive to a signal for beginning a cycle of movement of said piston of said cylinder (14, 15) in a first direction; a signal in response to movement of the sprayer (S) into overlying relation to the glass containers (C) to energize the sprayer (S), a signal to deenergize the sprayer (S) when the sprayer passes the conveyor (10) in said first direction, a signal when the piston approaches the end of its movement in one direction to energize an air brake; and a signal when the piston reaches the end of its movement to energize the actuator means (21, 22) for pivoting said arm (1); and a signal for reversing the operation of the cylinder (14, 15) to move the sprayer (S) in a second direction toward the initial position; a signal for energizing the spray apparatus as the sprayer (S) is moved into overlying relation to the containers (C), a signal for deenergizing the sprayer (S) when the sprayer passes the conveyor (10) in said second direction; and a signal responsive to the approach of the piston to its original position to apply an air brake to slow the speed of the piston. A method of applying surface coatings to glass containers (C), including the steps of a) moving a conveyor (10) in longitudinal direction with a velocity V 1 = R/T r , where R is the center line distance between rows of containers, and T r is the time to advance for one row (one cycle); b) activating a sprayer (S) and moving same across the conveyor (10) in one cycle period and along a line (4), which is in an acute angle (α) to the transverse axis of the conveyor, and simultaneously spraying onto said row of containers (C); characterised by: c) deactivating the sprayer (S) and shifting same a row distance (R) back, seen in moving direction of the conveyor (10), d) activating the sprayer (S) and moving same across the conveyor (10) in another cycle period in opposite direction to step b) and along a line (5) which is at an acute angle opposite to the acute angle (α) of step b) in relation to the transverse axis of the conveyor, and simultaneously spraying onto said row of containers (C), e) repeating steps b), c) and d) while advancing the conveyor (10) according to step a).

Inventors: DEMBICKI MICHAEL T, POAD WILLIAM J, WANSON THOMAS E, DEMBICKI MICHAEL T., POAD, WILLIAM J., WANSON THOMAS E.
Applicants: OWENS BROCKWAY GLASS CONTAINER, OWENS-BROCKWAY GLASS CONTAINER INC.
Application year: 1994
Main classification: B05B13
IPC codes: B05B13